Comparative genomics of Bacillus thuringiensis phage 0305φ8-36: defining patterns of descent in a novel ancient phage lineage

Table 1 Divergence of homologous proteins of 0305φ8-36 and BtI1 compared to divergence among T4-like phages

Terminase (large subunit)	D (%)¹	Portal	D (%)¹
0305φ8-36 vs. BtI1	69	0305φ8-36 vs. BtI1	57
0305φ8-36 vs. KPP95²	72	0305φ8-36 vs. HF1 gp94	77
T4 vs. P-SSM2	65	T4 vs. P-SSM2	62
*Capsid*		*Sheath*
0305φ8-36 vs. BtI1	60	0305φ8-36 vs. BtI1	71
0305φ8-36 vs. b.p. 37 orf013	79	0305φ8-36 vs. HF2p095	79
T4 vs. P-SSM2	65	0305φ8-36 vs. KVP40	84
		T4 vs. S-PM2	63
*Helicase*		*Primase*
0305φ8-36 vs. BtI1	58	0305φ8-36 vs. BtI1	69
0305φ8-36 vs. Nil2	76	0305φ8-36 vs. phBC6A51	73
T4 gp41³ vs. P-SSM2	58	T4 gp41³ vs. S-PM2	68

¹Divergence is (100 – percent identity) from a Psi-Blast alignment. Divergence was not corrected for saturation.
²Phage hosts are as follows: HF1 – Halobacterium; KPP95 – Klebsiella; P-SSM2 -Prochlorococcus (a cyanobacterium); S-PM2 – Synechococcus (a cyanobacterium); Bacteriophage 37 – Staphylococcus; phBC6A51 – putative prophage of Bacillus cereus; Nil2 – prophage of Escherichia coli.
³Residues 179–382 of T4 gp41 were used for the helicase comparison, and 1–178 for the primase.

ISSN: 1743-422X